Connecting a auto excited alternator to Lehman 120

[Mgtgrafix]

Hey guys ..
I had to replace my alternator and went with a Leece Neville MR8 90 amp alternator. It does not have a connection to connect to my oil pressure switch on my Ford Lehman 120. Can someone explain how I should connect the pressure switch?

 

[Comodave]

What regulator do you have? Some of the smart regulators have a time delay before they start putting out a charge in order to let the engine get running.

 

[Mgtgrafix]

I do not have a regulator

 

[FF]

The wire to power the field terminal is usually used as an off/on switch.

 

[psneeld]

Pretty sure you no longer connect it to the Oil switch.


I dont.


Just battery, negative and tachometer to one of the small AC posts if you have that kind of tach.


Now you can use the oil pressure switch for an electric fuel pump possibly.


Note: I since replaced the too small black DC neg wire as it showed signs of heat stress after a couple hundred hours.

 

[Mgtgrafix]

Pretty sure you no longer connect it to the Oil switch.


I dont.


Just battery, negative and tachometer to one of the small AC posts if you have that kind of tach.


Now you can use the oil pressure switch for an electric fuel pump possibly.


Note: I since replaced the too small black DC neg wire as it showed signs of heat stress after a couple hundred hours.

Could you show a pic of your oil pressure switch and what it is connected to? I still have the connection to the buzzer but do I just not connect the other wires?

 

[psneeld]

My oil pressure switch that connected to the alternator was not connected to anything else. So now it just sits there with nothing connected to the terminals.


So I have no idea how your setup is wired and without seeing it I cannot suggest anything.

 

[Comodave]

The oil pressure switch that is connected to the alternator isn’t for the oil pressure alarm. It is there so the alternator doesn’t load the engine while it is starting. It stops the alternator from putting out current until the engine gets running and has oil pressure.

 

[Mgtgrafix]

The oil pressure switch that is connected to the alternator isn’t for the oil pressure alarm. It is there so the alternator doesn’t load the engine while it is starting. It stops the alternator from putting out current until the engine gets running and has oil pressure.

Oh ok. I will be down at the boat tomorrow so I will snap a pic. But it sounds like I can just keep it disconnected. Should I disconnect the buzzer wire?

 

[psneeld]

Why don't you take a picture for us to see what you have. Without it everyone is just guessing. Make sure we can see all sensors from alternator to starter.

My oil pressure switch was right behind the alternator. The pressure switch and alarm sensor for the instrument guage panel are further aft under where the air intake is.

 

[Mgtgrafix]

Will do. I will take a pic tomorrow